Conmute Time, Headache for SC4 builders

I have been thinking how to increase the population of my regions, I wanted to discover how to increase large-size-city population. At Truna's project, the idea was to provide a web of freeways, avenues and roads, and public transportation of metro and buses, but car remained as the first way of transportation. Conmute time was reduced but air pollution increased dramatically.

Then I realized that Truna's population was very low for the size of region used. with the equivalent of 46 squirt kilometers Truna had a bit more than 1'550,000 sims. it means a bit more of 33,600 sims per/squirt km. I wanted this population to be increased.